    <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
       {# 公司logo #}
       {% load static %}
        <a href="http://10.1.1.80:8000" class="float-left"><img src="{% static "images/logo_long_new.png" %}" height="50" width=auto></a>

      <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
        <span class="navbar-toggler-icon"></span>
      </button>

      <div class="collapse navbar-collapse" id="navbarSupportedContent">
        <ul class="navbar-nav mr-auto">
          <li class="nav-item active">
            <a class="nav-link" href="/">主页<span class="sr-only">(current)</span></a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/top">拓扑图</a>
          </li>
          <li class="nav-item dropdown">
            <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              设备监控
            </a>
            <div class="dropdown-menu" aria-labelledby="navbarDropdown">
              <a class="dropdown-item" href="/monitordevice/cpu">CPU利用率监控</a>
              <a class="dropdown-item" href="/monitordevice/mem">内存利用率监控</a>
              <a class="dropdown-item" href="/monitordevice/if_speed">接口速率监控</a>
              <a class="dropdown-item" href="/monitordevice/if_utilization">接口利用率监控</a>
            </div>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/adddevices">添加设备</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/showdevices">我的设备</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/deviceconfig">设备配置备份</a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="/netflow/">Netflow协议分析</a>
          </li>
          <li class="nav-item dropdown">
            <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              日志系统
            </a>
            <div class="dropdown-menu" aria-labelledby="navbarDropdown">
              <a class="dropdown-item" href="/log/elk">ELK集成</a>
            </div>
          </li>
          <li class="nav-item dropdown">
            <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              自动化剧本
            </a>
            <div class="dropdown-menu" aria-labelledby="navbarDropdown">
              <a class="dropdown-item" href="/playbook/find_if">找到IP所在接口</a>
            </div>
          </li>
          <li class="nav-item dropdown">
            <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              系统设置
            </a>
            <div class="dropdown-menu" aria-labelledby="navbarDropdown">
              <a class="dropdown-item" href="/sysconfig/lifetime">数据库老化时间</a>
              <a class="dropdown-item" href="/sysconfig/monitor_interval">监控周期</a>
              <a class="dropdown-item" href="/sysconfig/threshold_mail">监控阈值与邮件通知</a>
              <a class="dropdown-item" href="/sysconfig/netflow">Netflow相关设置</a>
              <a class="dropdown-item" href="/showdevicetypes">设备类型清单</a>
            </div>
          </li>

        </ul>
        <form class="form-inline my-2 my-lg-0" action="/accounts/logout">
          <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Logout</button>
        </form>
      </div>
    </nav>